Emergency Radiology

The objective of the study is to describe the causes of cardiac arrest and complications of cardiopulmonary resuscitation (CPR) on thoraco-abdominal CT examinations for resuscitated patients in our institution. We evaluated the causes of cardiac arrest on thoraco-abdominal CT scans, which was compared with the final diagnosis (determined by consensus of two emergency physicians based on the clinical, imaging, and laboratory findings). Additionally, we evaluated the complications of CPR on thoraco-abdominal CT scans. From March 2005 to August 2011, 82 patients underwent CT of the thorax (n = 77) and abdomen (n = 23) within 24 h after CPR. Final diagnosis was as follows: cardiac (n = 29), respiratory (n = 28), metabolic (n = 11), exsanguination (n = 5), cerebral (n = 2), sepsis (n = 1), and indeterminate (n = 6). In 25 patients (30 %), thoraco-abdominal CT scans made the role either as a definitive study (n = 22) or as a supportive test (n = 3) for the diagnosis. In particular, CT was critical in diagnosis of many respiratory causes (64 %) and all exsanguinations. The most common complications following CPR were skeletal chest injuries (n = 48), followed by lung contusion (n = 45). Thoraco-abdominal CT examinations are helpful for the diagnosis of cause of cardiac arrest and complications of CPR.

This investigation evaluates the impact of the no oral contrast abdominopelvic CT examination (NOCAPE) on radiology turn around time (TAT), emergency department (ED) length of stay (LOS), and patient safety metrics. During a 12-month period at two urban teaching hospitals, 6,409 ED abdominopelvic (AP) CTs were performed to evaluate acute abdominal pain. NOCAPE represented 70.9 % of all ED AP CT examinations with intravenous contrast. Data collection included patient demographics, use of intravenous (IV) and/or oral contrast, order to complete and order to final interpretation TAT, ED LOS, admission, recall and bounce back rates, and comparison and characterization of impressions. The NOCAPE pathway reduced median order to complete TAT by 32 min (22.9 %) compared to IV and oral contrast AP CT examinations (traditional pathway) (P < 0.001). Median order to final TAT was 2.9 h in NOCAPE patients and 3.5 h in the traditional pathway, a 36-min (17.1 %) reduction (P < 0.001). Overall, the NOCAPE pathway reduced ED LOS by a median of 43 min (8.8 %) compared to the traditional pathway (8.2 vs 7.5 h) (P = 0.003). Recall and bounce back rates were 3.2 %, and only one patient had change in impression after oral contrast CT was repeated. The NOCAPE pathway is associated with decreased radiology TAT and ED LOS metrics. The authors suggest that NOCAPE implementation in the ED setting is safe and positively impacts both radiology and emergency medicine workflow.

First- and second-rib fractures diagnosed on plain radiographs have been associated with traumatic aortic injury. We examined whether such fractures diagnosed on computed tomography (CT), which is of greater sensitivity than plain radiograms for rib fractures, are associated with traumatic vascular injury. We identified 1,894 patients who had undergone a chest CT angiogram with indication of trauma between 2005 and 2008. Among these, 185 patients were selected at random. The main mechanism of injury was motor vehicle accident or a fall. The patients were divided into two groups: patients with first- and/or second-rib fractures and those without. Proportions of patients with major vessel injury noted on CT angiography were compared between groups. Information regarding displacement of the fracture, location of the fracture, detection upon plain film, and gender of the patients was also evaluated and correlated with incidence of major vessel injury. Fisher’s test and χ2 analysis were used to determine significance of the data. Incidence of major vessel injury was similar between patients with and without first- and/or second-rib fractures (7% vs. 9%, respectively; p = 0.59). No subset of type of rib fracture was associated with greater incidence of aortic injury. First- and second-fractures are not associated with greater incidence of aortic injury. Thus, the previous axiom that first- and second-rib fractures should result in increased examination for aortic injury may not hold true.

Abdominal wall hernias are a common abdominal pathology with higher prevalence in our population. It is usually asymptomatic but complications such as strangulation, incarceration or bowel obstruction need early detection and emergency surgery. The purpose of this article is to describe the infrequent type of hernia, illustrate the imaging findings and review the differential diagnosis. A 76-year-old woman was admitted in the emergency room with abdominal pain, vomits and diarrhoea. At her admission, a colonoscopy was attempted to perform but it was not possible to go beyond the stenosis. A barium enema and a multi-detector computed tomography (MDCT) were performed revealing a large mass in the left ischiorectal fossa, containing herniated loops of sigmoid colon adjacent to rectum. Abdominal wall hernias occur at areas of congenital or acquired weakness in the abdominal wall and are considered external hernias. MDCT is essential to identify wall hernias, make an accurate diagnosis and help for its clinical assessment. Knowing the radiological features of various types of abdominal hernias on MDCT and barium-enhanced radiographs allows confident diagnosis of these pathologies.

Excessive obesity poses a significant limitation to radiographic magnetic resonance imaging (MRI), particularly related to aperture or bore diameter due to the patient’s girth. Determination of whether a patient will fit into the bore of the MRI scanner is currently accomplished using patient height, weight, and MRI technician experience. These simple methods have proven unreliable. We sought to develop a device and method which could accurately determine whether a patient would fit into the MRI scanner. We developed an MRI template prototype which was tested against the standard radiology methods in a pilot study (n = 6). We then performed a prospective validation study in adult human volunteers (n = 100) to assess the accuracy of the MRI template. We collected height, weight, shoulder and pelvis girth/diameter for each study participant to evaluate the body dimension measurements that would assist in determination of whether a patient would fit into the MRI scanner. Using the MRI template, we determined that 11 of the 100 study participants would not fit in the MRI scanner and 10 were confirmed to not fit into the MRI aperture [positive predictive value (PPV) 0.91 (0.58–0.99); negative predictive value (NPV) 1.00 (0.95–1.00), sensitivity 1.00 (0.69–1.00), specificity 0.99 (0.93–0.99), likelihood ratio positive test 90 (12.81–632), likelihood ratio negative test 0, accuracy 99%]. In comparison, the body measurement method did not perform as well [PPV 0.66 (0.34–0.90), NPV 0.97 (0.92–0.99), sensitivity 0.80 (0.44–0.97), specificity 0.95 (0.89–0.98), likelihood ratio positive test 17.97 (6.56–49.2), likelihood ratio negative test 0.209 (0.06–0.72), accuracy 94%]. This study confirmed that the use of an MRI template is an accurate tool in determining whether an obese patient can fit through the MRI bore and be accommodated in the MRI scanner.

This is the 44th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at: http://www.erad.org/page/CCIP_TOC.